1. Field of the Invention
This invention relates to a paper guide mechanism for a serial printer including an ink ribbon guide plate and a paper guide plate by which print paper is kept from being soiled by an ink ribbon.
2. Description of the Related Art
Conventionally, a paper guide plate and an ink ribbon guide plate mounted on the paper guide plate are generally flat in sectional view. The ink ribbon guide plate is set in a gap between a platen and a print head. If the gap between the print head and the ink ribbon guide plate is made comparatively large, the ink ribbon guide plate is displaced toward the platen. Consequently, the entire faces of the ink ribbon guide plate and the paper guide plate are liable to come in contact with print paper on the platen. On the contrary, if one decreases the gap between the ink ribbon guide plate and the platen, then the gap between the print head and the ink ribbon guide plate is narrow so that the ink ribbon becomes liable to leap out from a printing hole which is formed in the ink ribbon guide plate thereby allowing the print head to contact therethrough with the print paper on the platen with the ink ribbon interposed therebetween.
Since the sectional shape of the conventional paper guide plate on which the ink ribbon guide plate is mounted is generally flat and, depending upon the position of the ink ribbon guide plate set in the gap between the platen and the print head, either the entire faces of the ink ribbon guide plate and the paper guide plate are brought into contact with the paper so that the print paper is soiled by the ink ribbon or the ink ribbon leaps out from the ink ribbon guide plate. As a result, the positioning operation to set the ink ribbon guide plate in position in the gap between the platen and the print head is quite difficult.